When two centrifugal pumps are connected in parallel with their inlet and outlet valves fully open, if one pump is started, will the other pump run in reverse?
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When two centrifugal pumps are connected in parallel with their inlet and outlet valves fully open, if one pump is started, will the other pump run in reverse?
Check – the check valve of the pump that is operating in reverse is broken.
Generally not, unless the check valve is broken, as mentioned above
This depends on the installation location of the check valve at the pump outlet. If each pump has its own check valve and those check valves do not allow leakage, then the pumps will not reverse direction. Some design institutes now provide drawings in which two pumps share one check valve, with this valve being installed on the common pipeline downstream of the outlets of both pumps; in such cases, the pumps will inevitably reverse direction.
Check whether there is a check valve at the pump outlet; if not, backflow will definitely occur. If there is a check valve, it may still cause backflow if it is damaged or not sealed properly, resulting in excessive leakage. A small leakage amount will not cause reversal
Yes, in severe cases it can damage the impeller; to prevent this, the valve of the pump that is not in use should be closed, or check valves should be installed at the outlets of both pumps